What organ is responsible for the exchange of oxygen and carbon dioxide?

The lungs are the primary organs responsible for the exchange of oxygen and carbon dioxide in the body. This process occurs in the alveoli, small air sacs located within the lungs. When you inhale, oxygen from the air enters the alveoli and diffuses into the blood, where it binds to hemoglobin in red blood cells for transport to the rest of the body. Simultaneously, carbon dioxide, which is a waste product of metabolism, diffuses from the blood into the alveoli to be exhaled. This vital exchange is essential for maintaining proper respiratory function and overall homeostasis.

In contrast, while the heart pumps blood throughout the body and plays a crucial role in circulation, it does not directly facilitate gas exchange. The kidneys are responsible for filtering blood and maintaining fluid balance but do not participate in respiratory functions. The liver has various metabolic roles, including detoxification and bile production, but like the kidneys and heart, it does not engage in the process of oxygen and carbon dioxide exchange.